I think that sidepods are made hollow from wrong side. I think that they should be hollow longitudinally like sidepods on karting. They way they look now on your pic they’ll cause drag and turbulence. If you can’t make them hollow all the way than make the hollow from rear to front.
I see one mayor reason for wrong perception of why some cars seams faster in observing the shape of car only. All cars have different wheels and same cartridge so, to know which car has better design you’d need to have all cars on equal wheels. The way things look now car with lower rolling resistance can easily outperform car with better aerodynamics and less weight but with wheels with higher rolling drag.
Anyway, having in mind short distance and low speeds these cars reach I still remain convinced that attempts to close as much of the car as possible in order to deal with drag caused by wheels is a wrong direction because weight of such car would highly exceed weight of slim open-wheel car that will be able to accelerate faster. To me that is the whole point – to achieve highest speed before the cartridge has emptied.
Not sure of the rules, but cant you make the thing hollow, with a type of cap that you can cover the bottom of the sidepods (and even the entire body)?
Again not sure about the rules - cant you sort that rear end out? I dont think those flat surfaces will help. Could you not merge the canister more to the chassis?
Apex wrote:Not sure of the rules, but cant you make the thing hollow, with a type of cap that you can cover the bottom of the sidepods (and even the entire body)?
Again not sure about the rules - cant you sort that rear end out? I dont think those flat surfaces will help. Could you not merge the canister more to the chassis?
Rules are strict – it must be made in one piece using CAD/CAM while only wings can be added separately.
It appears to improved from the previous generation.
I do have to wonder about that small vertical fin on the nose, what function does it do, and wouldn't it be a possible source of destailization at speed?
The integration of sidepods to cover the wheels looks to be in he right direction, but if it was my decision, I would make every effort to shield the airflow from all wheel contact. A raised lip, or even higher sidepods may be able the mask the airflow from negative wheel interference. I would also attampt to tuck the bodywork as close to the wheels as possible, very close.
The centerline of thrust of the gas bottle appears to be horizontal, thus giving downforce on the nose under acceleration. Is is possible under the rules to angle the center line of the bottle downwards, so that the front wheels are not pressed down as hard, thus reducing frictional drag?
Hollowing out the sidepods appears to be a good strategy, but why use the bottom? That just opens that part up to turbulence? I would suggest trying to hollow out the sidepods via the rear wheel cutouts. Much more difficult, but it may generate less turbulence, and less drag.
DaveKillens wrote:I do have to wonder about that small vertical fin on the nose, what function does it do, and wouldn't it be a possible source of destailization at speed?
I think that vertical fin it is my "invention" - whose purpose is to cut the finish line beam ASAP instead to wait for the part of the car high enough to break it...
DaveKillens wrote:]The centerline of thrust of the gas bottle appears to be horizontal, thus giving downforce on the nose under acceleration. Is it possible under the rules to angle the center line of the bottle downwards, so that the front wheels are not pressed down as hard, thus reducing frictional drag??.
I suggested that to someone before but Monstro said that best result requires horizontal position of cartridge... BTW, I think that regulations prohibit changing position and angle of cartridge.
Something that I just remembered from hill climb racing… I don’t know how this F1 school challenge is started but presuming that it goes from beam to beam than I’d consider using an old trick hill climb drivers use and that is positioning car as further as possible from start line beam (if the marshals are not paying attention). That enables the car to break the start line beam at higher speed than it would if it started directly behind the beam. A second here, a second there and you have a winner!
It would be nice to get a running start, but I think the rules would prohibit that.
Yes, it's desirable to have the thrust aimed directly along the axis of travel, any angle would diminish forward thrust. But I was wondering about the movement of the front wheels, and possible negative drag effects.
This is my visualization of what happens to the front end. Under initial acceleration, since the center of thrust is above the center of mass, the nose would be forced down. If there was any spring or flex in the axle or wheel, it would be compressed. The top of the wheel would project above the front fairing, allow a slight amount of drag. As well, the entire vehicle may be inclined enough to generate drag, since it would not be moving totally horizontal relative ot the "road" surface. As soon as the cartridge runs out of gas, thrust stops, and the front end would spring up and probably have the nose higher than planned. It would also probably rub with force against the guide string, adding drag.
I would suggest running tires that are hard, with no bounce or flex. Additionally, make every effort to make sure the axle has as little flex as possible, by either making it of stiff material, or larger diameter, or a combination of both. Also, the distance from the body attachment points and wheel should be as small as possible, to try to take axle flex out of the equation. Also, don't trust the body attachment points, since the body is made out of balsa, and soft. An axle that flexes would probably push through the balsa, still giving some flex.
